Assisted Hatching


The normal process of conception requires escape or “hatching” of the early embryo from the zona pellucida shell. Hatching usually occurs around the 5th or 6th day following fertilization and is required for the embryo to attach, or implant, in the uterus. Inability of the embryo to complete the hatching process may interfere with implantation. Assisted hatching is a laboratory procedure designed to reduce the chance that an embryo will be unable to proceed beyond this stage.

Some studies suggest that IVF success rates are improved if assisted hatching is performed, particularly in older women. The ART program may recommend assisted hatching in select circumstances that include advanced maternal age or previous IVF failure.

Assisted hatching is accomplished by creating a small hole in the zona pellucida, either by the focal application of a special solution or by the energy from a focused laser beam. Similar to many aspects of handling and manipulating embryos in vitro, there is risk of damage to the embryo resulting in the loss of viability (life). This risk is very low.